Pretend for a moment that we wanted to forcibly reduce the production of carbon dioxide by Australians.

There are three ways to do it.

The first option is to levy a tax on every tonne of carbon dioxide produced. This assumes that if you tax something, less of it will be produced. This is phase 1 of the Gillard/Greens scheme. Tax payers rate this the “least worst” scheme because it is simple, easily demonised and easily abolished once it becomes obvious that it is achieving no climate benefits at great cost.